like the low angle you took many of your photobucket shots in. It gives the bike a nice power appearance and making them look larger and more impressive of a machine.
I like the one with gsxr and the cheeseburger in paradise sign.
The first photo with the R6, I do not get what you were trying to say.
i can see the menacing look for #1, but the white balance being off on the whole shot distracts as well as it being a little too closely cropped particularly on the bottom.
#2 is my favorite here. i really like the low angle and the inclusion of the neon sign in the background, especially when you get a chance to process it, a little work on the levels/curves and some sharpening will give it some extra pop.
#3, pretty standard, nothing too exciting
#4 i can see you are going for something different, but the light just dominates too much.